MEXICO CITY (AP) — High-ranking Mexican security officials are portraying the shooting of two CIA agents by Mexican federal police as a well-intentioned mishap rather than a deliberate attack.

A series of military and law-enforcement officials have emphasized in public statements over the last three days that the group of 12 federal police was investigating a kidnapping when they encountered the two U.S. agents and a Mexican marine captain and opened fire on their armored sport-utility vehicle.

U.S. and Mexican statements released on the day of the shooting contained few details, excluding mention of the kidnapping probe. As a result, they left open the possibility that it could have been a deliberate attack on the Americans by corrupt officers or a gross error by well-intentioned but trigger-happy police conducting legitimate work in a dangerous rural area outside the city of Cuernavaca.

Mexican officials declined to elaborate for more than a week after the shooting, but now appear to be trying to be making a case for the accidental scenario.

Navy Secretary Mariano Francisco Saynez told reporters after President Felipe Calderon’s last state-of-the-union address on Monday that the attack “was an error and not a malicious act.” The statement carried particular significance coming from the highest-ranking officer in the navy, the military branch that includes the marines.

Interior Minister Alejandro Poire said Tuesday that federal police officials were investigating a kidnapping that had taken place a day earlier near the scene of the shooting. He wouldn’t give any other details Tuesday “out of respect for the kidnapping victim.” The assertion that the officers were investigating a specific crime around the village of Tres Marias would appear to undercut the idea suggested by some experts that they had gone there knowingly targeting the U.S. agents and marine captain.

Federal Police regional security chief Luis Cardenas Palomino also told reporters over the weekend that agents were investigating a kidnapping before the shooting. A lawyer for two of the police has said they were looking for the kidnappers of a businessman, thought the diplomatic car was involved, and the shooting erupted after the agents refused to obey a federal police order to halt.

In the official U.S. account of the attack, released hours after the shooting, the U.S. Embassy in Mexico City said the diplomatic vehicle was “ambushed by a group of individuals,” a term that implies that the federal police were lying in wait for the agents and marine captain. U.S. Embassy officials declined to comment Tuesday, saying only that the U.S. was cooperating with Mexico in the investigation of the shooting.

The federal police officers were ordered detained under a form of house arrest for 40 days on suspicion of abusing their authority. That charge can entail both criminal wrongdoing and extreme negligence.